Iran, the world's fifth-largest crude oil exporter, is under pressure to cease its nuclear program as the West steps closer to imposing a tougher sanctions regime on the Islamic republic.
The following are some details about Iran's principal energy partners and joint projects:

* CHINA

- Iran is the third-largest crude oil supplier to China. For the whole of 2009, China imported some 460,000 barrels per day (bpd) of crude from Iran, about 15 percent more than contracted supplies.

- In 2010, Zhuhai Zhenrong Corp, the world's largest single lifter of Iranian crude, agreed to purchase 240,000 bpd from the OPEC member. The levels were similar to the 2009 supply deal. Zhenrong supplies most of the Iranian oil it purchases to China's Sinopec Corp, Asia's largest refiner.

- Sinopec has extended a separate purchase deal for 2010 with the National Iranian Oil Company (NIOC), with volumes steady or higher than the estimated 160,000 bpd levels in 2009.
China, Asia's No.1 fuel oil buyer, has reduced most of its fuel oil imports from Iran. Traders said China cut purchases due to what it saw as uncompetitive prices from Iran. In 2009, China's Iranian fuel oil imports fell 64 percent to 434,000 tonnes.

- China's National Petroleum Corporation (CNPC) clinched a $4.7 billion deal this year to develop phase 11 of its South Pars, replacing France's Total. CNPC beefed up its staff in Iran late last year to around 60, even as western oil firms scaled down their staff.

- CNPC signed a $2 billion, 12-year deal with the National Iranian Oil Company in 2009 to develop the North Azadegan oilfield to boost capacity there to 120,000 bpd.

- CNPC signed a memorandum of understanding for development of the South Azadegan field in July 2009. Under that deal, it would pay 90 percent of the costs of a $2.5 billion project.

- CNPC is in talks with Iran for a $3.6 billion deal to buy LNG from Phase 14 of South Pars project. CNPC is also in talks to explore and develop energy reserves in Iran's Caspian.

- China's Sinopec Group finalised a $2 billion pact to develop Iran's huge Yadavaran field in December 2007.

- The China National Offshore Oil Corp (CNOOC) is in talks to finalize a $16 billion deal to develop the North Pars gas field and build a liquefied natural gas (LNG) plant.

* INDIA

- India imported 426,360 bpd of Iran's oil in the fiscal year 2008/09, or 9.5 percent more crude versus a year earlier.

- Reliance Industries will cease imports from Iran in the new financial year, while Mangalore Refinery and Petrochemicals Ltd will cut imports from Tehran by 8.5 percent to 130,000 bpd for 2010/11.

- In December Iran offered Indian firms ONGC, the Hinduja Group and Petronet LNG a 40 percent interest in the development in the South Pars Phase 12 project and Iran LNG. ONGC has said it was studying the viability of the proposals and would follow New Delhi's policy on Iran.

- India had been part of the $7 billion so-called 'peace pipeline' gas project, but stayed away from talks last year as it wanted a bilateral deal with Pakistan on transit costs first. Iran said in May India could still join the project.

* JAPAN

- In 2009, Iran exported about 421,000 bpd of crude to Japan. It was overtaken by Qatar, however, as Japan's third-largest crude supplier.

- Many of Japan's top refiners buy Iranian crude, including Showa Shell Sekiyu, Nippon Oil, Japan Energy, Cosmo Oil. Trading house Toyota Tsusho also has a deal to buy crude from the Islamic republic.

- Many of these refiners have cut back on their imports from Iran as the country's oil demand has contracted. Japanese refiners have cut processing runs due to low profit margins.

- Japan's INPEX holdings saw its 75 percent stake in Iran's huge Azadegan oilfield cut to 10 percent in 2006 when talks fell through on a development plan.

* SOUTH KOREA

- In 2009 Iran exported 81,446 bpd of crude to South Korea, 12 percent up versus the previous year, while maintaining its rank as South Korea's fourth-largest crude supplier after Saudi Arabia, the UAE and Kuwait, according to the data from Korea National Oil Corp.

- South Korea's top refiners which buy Iranian crude include SK Energy and Hyundai Oilbank.

* MALAYSIA

- Malaysia's SKS group signed a gas deal worth $14 billion with NIOC in December 2008.
The deal involves a project to produce LNG and the development of two gas fields, Golshan and Ferdowsi. Exports of crude and 120,000 barrels of gas condensates are also part of the agreement.

- State oil firm Petronas remains one of the principal suppliers of gasoline to Iran.

* INDONESIA

- State oil firm Pertamina said in March 2009 a refinery joint venture project with Iran may be delayed until 2016 from 2010. In 2006, Pertamina's unit PT Elnusa signed a preliminary deal with National Iranian Oil Refining and Distribution Company to build a 300,000-barrels-per-day oil refinery in Indonesia.

* RUSSIA

- Russia is building Iran's first nuclear power plant and supplying the fuel it will use.

- Russia state controlled energy giant Gazprom agreed in February 2009 to take on new projects in Iran, including a bigger role in South Pars and drilling for oil. Gazprom has invested about $4 billion in Iran since 2007 and was involved in an earlier phase at South Pars.

* FRANCE

- Oil giant Total was replaced by China's CNPC on the South Pars field in 2009. The French major is also a key supplier of gasoline to Iran, along with Malaysia's Petronas.

* ITALY

- Prime Minister Silvo Berlusconi said in February that ENI SpA had cancelled an unspecified third development phase in Iran, which analysts said was the Darkhovin field. An Iranian official later said ENI had not withdrawn.

* GERMANY

- In 2006, Germany's ABB Lummus signed a $512 million contract with NIOC and a consortium of Iranian companies to develop the Bandar Abbas refinery. The group intends to raise gasoline production to 13 million litres per day from 4.8 million litres currently.

* POLAND

- Polish gas monopoly PGNiG has signed a preliminary deal with Iran's Offshore Oil Company to cooperate on managing already-discovered gas reserves.

* SPAIN

- Repsol had planned to participate with Shell in developing South Pars and building an LNG plant, but Shell pulled out in 2008. Iran had given a deadline last May for Shell and Repsol to clarify their involvement in the project.

* SWITZERLAND

- Swiss energy group EGL signed a 25-year gas purchase deal worth over $13 billion with Iran last year.

* TURKEY

- Turkey signed a preliminary deal in November 2008 for gas to be exported to Europe through Turkey and for Turkey to produce gas in the South Pars field. The investment would amount to $3.5 billion.

* UNITED KINGDOM

- Oil major Royal Dutch Shell pulled out of Phase 13 of the giant South Pars gas field in 2008 but said it may yet join later development stages there.